If you want Java working in Firefox 12, you must have Java 6 Update 32 installed because it says Java 7 Update 3 is "outdated" and disables it.
So you need another 100 megabytes of software on your PC just to satisfy Firefox.

IE8, IE9 and whatever the latest version of Google chrome is have no problems with Java 7.
That's a classic programming mistake, not properly coding for the "or later/higher/newer" condition so the program assumes something with a higher version number (by numeral or letter) is NOT newer and acceptable.
I ran into that a few times with programs that insisted DirectX 9.0c was "too old" and demanded DirectX 9.0, 9.0a, or 9.0b. I've also run into the same problem with some other components and additions to windows where the latest version was rejected as "too old".
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Fandemonium!August 3rd, 4th and 5th, 2012
"I am a machine. I am a weapon of war. I am a destroyer of life in the service of life, the sword and shield of my human creators." Bolo
Invincibilus, Mark XXIII, Model B (Experimental) 0075-NKE "Nike".